package com.itheima.demo02.JDK9;

import java.util.List;
import java.util.Map;
import java.util.Set;

public class Demo01JDK9 {
    public static void main(String[] args) {
        List<String> list = List.of("a", "b", "a", "c", "d");
        System.out.println(list);
//        list.add("w");
        Set<String> set = Set.of("a", "b"/*, "a"*/, "c", "d");
        System.out.println(set);
//        set.add("w");
        Map<String, Integer> map = Map.of("张三", 18, "李四", 19, "王五", 20/*,"张三", 19*/);
        System.out.println(map);
//        map.put("赵四",13);
    }
}
